The present invention relates to a foldable wheelchair, and more particularly relates to improvement in operability and transferability of a wheelchair.
In the following description, the phrase "a user" refers to a person such as a sick patient, an elderly or a bodily crippled person who needs to use a wheelchair for travel between two distant spots.
Further, a term "longitudinal direction" refers to a horizontal direction extending front to rear on a wheelchair whereas a term "lateral direction" refers to a horizontal direction substantially perpendicular to the longitudinal direction.
A conventional wheelchair includes a pair of main frames spaced in the lateral direction by two or more transverse bars. The rear side of the wheelchair is closed by a back upholstery spanning upright pole sections of the main frames. A pair of large wheels are coupled to both lateral sides of the main frames. A pair of casters are also coupled to the main frames on the front sides of the associated large wheels. A pair of footplates are attached to the front lower ends of the main frames in a side-by-side arrangement whilst projecting forwards.
For movement of a wheelchair, its user may rotate the large wheels via push rims attached to the large wheels. Alternatively, a helper may push the wheelchair via handgrips attached to the back upholstery.
In either case, the relatively rigid construction of a wheelchair and presence of large wheels cause many inconveniencies in actual use of the wheelchair.
First, due to presence of the transverse bars spanning two main frames, it is almost impossible to bring the wheelchair as close as possible to the position of a user lying on a bed. So, for transfer of a user between a wheelchair and a bed, two or more helpers need to carry the user manually. This manual transfer not only poses much load on the helpers but, depending on the body condition of the user, causes much physical pain to the user.
Second, due to the presence of the two large wheels projecting sideways from the main frame, a wheelchair can go through only a toiled door or a bath door which is designed specially broad enough to allow its passage. Here again, the user needs assistance by two or more helpers.
The relatively rigid construction and presence of various accessories such as footplates make a wheelchair very unwieldy and such an unwieldy construction causes troublesome transportation of a wheelchair.